PP-g-GMA的制备及其改性PP/PA6合金性能

采用双螺杆熔融接枝的方法,在引发剂过氧化二异丙苯(DCP)作用下,将甲基丙烯酸缩水甘油酯(GMA)和共单体苯乙烯(St)接枝到聚丙烯(PP)上。通过傅立叶变换红外光谱仪确定了接枝物的生成,采用酸碱滴定法测定了接枝率。探讨了GMA,St,DCP不同用量对PP接枝物的接枝率和熔体流动速率的影响,并将接枝产物PP–g–(St–co–GMA)加入PP/尼龙6(PA6)的合金中,通过注塑成型样条,测定其力学性能,并观察微观结构。结果表明,St的加入能够提高接枝率,抑制副反应的发生。在PP/PA6合金中加入接枝物PP–g–(St–co–GMA),其拉伸强度可提高46.45%,弯曲强度可提高32.47%,但对冲击强度影响不大。     

PP-g-(DAP-co-GMA)和PP-g-(DAP-co-MAH)的制备及其增容PP/PET

以邻苯二甲酸二烯丙酯(DAP)为共单体,将马来酸酐(MAH)和甲基丙烯酸缩水甘油酯(GMA)分别接枝到聚丙烯(PP)上,制备了PP-g-(DAP-co-MAH)和PP-g-(DAP-co-GMA),考察了两种接枝物对PP/聚对苯二甲酸乙二酯(PET)增容性能的影响。结果表明:在MAH和GMA接枝PP过程中加入DAP作为共单体,可以明显地抑制接枝过程中PP的降解,提高GMA和MAH的接枝率;分别将两种接枝物加入到PP/PET共混体系中,与PP-g-(DAPco-MAH)增容体系相比,PP-g-(DAP-co-GMA)增容体系的共混扭矩、拉伸强度明显提高,PET熔点及玻璃化转变温度降低,PET分散更加均匀细小,两相相容性提高。     

玻璃纤维增强高结晶PP的研究

考察了玻璃纤维(GF)增强高结晶聚丙烯(PP)的力学性能,发现高结晶PP/GF的力学性能较普通PP/GF的提高15%～18%;同时考察了不同增容剂对高结晶PP/GF的力学性能的影响,均聚接枝物拉伸强度、弯曲强度较高,共聚接枝物的冲击强度较高;另外发现在PP/GF中加入山梨醇型α成核剂、芳酰胺类β成核剂后,两者对其性能有较大影响,使其力学性能降低40%以上。     

固相接枝共聚法制备PP—g—PS

用固相接枝共聚方法制备了聚丙烯接枝苯乙烯(PP-g-PS),详细地考察了聚丙烯与引发剂的品种、反应温度、苯乙烯及引发剂的浓度等因素对接枝率和接枝效率的影响。研究结果表明:PP-g-PS具有较高的接技率,应用于聚丙烯/聚苯乙烯(PP/PS)共混物中,能降低分散相PS的粒径,提高PP/PS的相容性。     

Nano-CaCO3/PP/PS复合材料的热降解行为的研究

用密炼机制备了马来酸酐接枝PP(MPP)和丙烯酸接枝PP(FPP)增容的nano-CaCO3/PP/PS复合材料,用TGA研究复合材料的热降解行为。结果表明:加入nano-CaCO3有助于提高PP/PS共混物的热稳定性,对于提高复合材料的热稳定性,FPP、MPP与nano-CaCO3不存在协同作用;nano-CaCO3/增容PP/PS共混物复合材料的DTG曲线在400℃~500℃间有两个失重速率峰,分别对应PS和PP的热降解。     

PP接枝聚合物对PP/PS共混物相形态的影响

通过原子转移自由基反应合成了聚丙烯(PP)接枝聚苯乙烯(PS) (PP-g-PS),研究了PP-g-PS对PP/PS共混物相形态的影响.采用扫描电子显微镜、偏光显微镜观察了共混物的断面形貌和等温结晶形态.结果表明: 加入PP-g-PS对PP/PS共混物起到了良好的增容作用,表现在两相界面模糊,分散相尺寸减小.当PP-g-PS中x(PS)为5.10% 左右时即可起到增容改善相界面的作用.相容性的提高改善了PP/PS共混物的发泡性能.     

增容剂对PP/PA66共混物力学性能和结晶行为的影响

采用熔融共混法制备了聚丙烯(PP)/聚酰胺66(PA66)共混物,研究了聚丙烯接枝马来酸酐(PP-g-MAH)和乙烯-辛烯共聚物接枝马来酸酐(POE-g-MAH)作为增容剂对PP/PA66共混物力学性能和非等温结晶行为的影响。结果表明:PP-g-MAH提高了共混体系的拉伸强度,加入5份POE-g-MAH能显著提高共混物的断裂伸长率;PA66可起到异相成核作用,使PP的结晶峰温度升高;加入PP-g-MAH进一步提高了PP的结晶峰温度;PA66使PP的结晶活化能增大,增容剂的加入则使共混体系中PP的结晶活化能降低。     

马来酸酐接枝物对PP/ABS复合材料性能的影响

在聚丙烯(PP)/丙烯晴-丁二烯-苯乙烯(ABS)复合材料中加入复配的马来酸酐接枝物(PP-g-MAH)和ABS-g-MAH,研究接枝物对复合材料性能的影响。结果表明:马来酸酐接枝物的加入能提高复合材料的拉伸强度和弯曲强度,并随着接枝物含量增加而提高,冲击强度随接枝物含量增加而降低。复配马来酸酐接枝物中在复合材料中PP-g-MAH的用量为10份时,综合性能最佳。PP/ABS复合材料的强度和刚度随ABS含量的增加而增加,随着ABS组分含量的增加,ABS相分布从海-岛状分布向海-海结构转变。SEM结果表明:马来酸酐接枝物的加入有助于ABS在聚丙烯中的分散;DSC数据表明:马来酸酐接枝物使材料的结晶度有所提高。     

双单体接枝物增容PP/EVOH共混物形态结构及性能

采用反应型双螺杆挤出机制备了双单体接枝物聚丙烯（PP）接枝马来酸酐（MAH）和三烯丙基异氰脲酸酯（TAIC）[PP-g-(MAH-co-TAIC)],并以此增容PP/乙烯-乙烯醇共聚物（EVOH）共混物。研究了共混增容体系的相容性、流变性能、结晶性能、力学性能和阻隔性能。红外光谱分析表明, 接枝物加入后,在EVOH的羟基和接枝物的酸酐基团之间发生了反应,体系的相容性因此得以改观;TAIC的加入使PP的接枝率提高了13 %;扫描电子显微镜观察证实,接枝物的加入促进了EVOH和PP之间的界面结合,减小了分散相的尺寸。流变性能测试表明,TAIC的加入抑制了PP的降解;差示扫描量热仪分析表明,接枝物的加入使得PP和EVOH的结晶温度得到了提高。双单体接枝物的共混体系与单一单体接枝物的共混体系相比,对力学性能影响不大,但阻隔性能有所提高,当共单体添加量为0.4份（质量份,下同）时,体系的阻隔性能提高了28 %。     

新型多单体接枝物增容PP/PVC共混体系的研究

自制了多单体接枝物PP g (St co MMA) ,并利用其增容PP/PVC共混体系。讨论了共混物组成、相容剂用量在不同温度、不同压力下对其流变行为的影响。实验结果表明 ,在所研究的温度和压力范围内 ,加入PP g (St co MMA)增容PP/PVC共混体系后 ,共混物熔体呈典型的假塑性流体特性 ,粘流活化能增加 ,非牛顿性有增大的趋势。共混体系的力学性能提高 ,SEM照片证明了多单体接枝物对PP/PVC的增容作用     

MAH—g—PP孚L液对PP／GF复合材料界面的影响

利用自制的MAH—g—PP乳液和KH-550溶液组合进行玻纤的表面处理。考察了MAH—g—PP乳液和KH-550溶液处理对PP／GF界面粘结的影响,研究了MAH—g—PP乳液处理玻纤表面的适宜温度和时间,探讨了MAH—g—PP乳液对PP／GF的偶联机理。结果表面：玻纤表面经MAH—g—PP乳液和KH-550溶液处理后,在PP／GF界面上形成了牢固的化学键连接,出现了明显的横晶层;MAH—g—PP乳液处理玻纤表面的适宜温度和时间为105℃、1h;MAH—g—PP乳液对PP／GF的偶联机理为乳液中的羧基与玻纤表面KH-550的氨基发生化学键合。     

马来酸酐及苯乙烯同时接枝聚丙烯的研究

用过氧化二异丙苯(DCP)作为引发剂，采用双螺杆反应挤出的苯乙烯、马来酸酐2种单体同时接枝聚丙烯．研究了单体总浓度、单体比例、引发剂浓度对PP的接枝率、接枝效率和熔体流动速率的影响。通过实验发现苯乙烯的加入使接枝率和接枝效率比单独的马来酸酐接枝都有很大的提高。     

马来酸酐接枝聚丙烯的进展

马来酸酐接枝聚丙烯是拓宽聚丙烯应用领域的重要手段之一,本文综述了马来酸酐接枝聚丙烯的接枝方法和原理,接枝物的性能以及接枝物在聚丙烯合金和共混物、复合材料、粘合剂和涂料领域的广泛应用。     

聚烯烃接枝马来酸酐的反应挤出研究

研究了聚乙烯（PE），聚丙烯（PP）接枝马来酸酐（MAH）的反应挤出，进行了反应体系的热分析，讨论了引发剂过氧化二异丙苯（DCP）和PE／DCP和PP／DCP体系的影响，以及DCP、MAH和电子给予体（EDA）和LDPE／DCP／MAH和PP／DCP／MAH两种接枝体系的影响。     

反应性相容剂的制备及其在PP/玻璃纤维复合材料中的应用

以马来酸酐(MAH)为接枝单体、丙烯酸-2-羟乙酯为共聚单体,利用熔融接枝技术对聚丙烯(PP)进行改性;以MAH/丙烯酸-2-羟乙酯熔融接枝改性PP为相容剂,研究相容剂对PP/玻璃纤维复合材料结构和性能的影响。结果表明:与未接枝PP相比,熔融接枝PP分子上接枝了MAH和—OH基团,而且熔融接枝反应对PP的熔点和热稳定性具有明显影响。另外,随着接枝PP含量的增加,PP/玻璃纤维复合材料的力学性能明显改善。当接枝PP含量为15%时,复合材料的拉伸强度提高了32%,冲击强度提高了13%,表明采用熔融共接枝工艺制备的PP具有优良的增容、偶联和分散效果。     

马来酸酐苯乙烯双单体接枝聚丙烯的研究

研究了聚丙烯（ＰＰ）采用熔融法接枝马来酸酐（ＭＡＨ）聚乙烯（Ｓｔ）双单体。实验表明,马来酸酐接枝率随其加入量增加而提高;添加两种单体时,马来酸酐添加量保持不变,马来酸酐接枝率随苯乙烯添加量增加而提高。经转矩流变,红外,热失重和差示扫描量热分析表明：马来酸酐,苯乙烯均与聚丙烯发生接枝反应,且有交联网络出现,因此推断出苯乙烯和马来酸酐预先发生交替共聚,共聚物与聚丙烯反应生成最终接枝物。接枝物应用于ＰＰ     

GMA/St双组分单体熔融接枝聚丙烯的研究

分别以甲基丙烯酸缩水甘油酯（GMA）和马来酸酐（MAH）为接枝单体，苯乙烯（St）为接枝共单体，过氧化二异丙苯（DCP）为引发剂对聚丙烯（PP）进行熔融接枝，研究了接枝单体的种类、组分配比等因素对PP的接枝率和熔体流动速率等的影响，并研究了接枝PP的力学性能和耐热变形性能。实验结果表明：作为接枝单体，GMA比MAH更具有优越性；双组分单体熔融接枝PP的接枝率和性能优于单组分单体熔融接枝；接枝PP的结晶参数受其接枝率的影响；当PP／GMA／St／DCP=100／6／3／0、3时，PP—g^-（GMA—CO—St）的接枝率最高，力学性能和耐热变形性能最好。     

Blends of i‐PP and SBS. II. Influence of in situ compatibilization on the mechanical properties

This article concerns the in situ compatibilization of immiscible isotatic polypropylene/styrene–butadiene–styrene triblock copolymer blends (i‐PP/SBS) by use of a reactive mixture. For this purpose, maleated PP (PP–MAH) and SBS (SBS–MAH) were used as functionalized polymers and 4,4′‐diaminediphenylmethane was used as a coupling agent between maleated polymers, resulting in a graft copolymer. Binary blends of i‐PP/SBS, nonreactive ternary blends of i‐PP/PP–MAH/SBS, and reactive ternary blends of i‐PP/PP–MAH/SBS–MAH with varying diamine/anhydride molar ratios were prepared. The mechanical properties of the blends were determined by tensile and impact‐resistance tests. The optimum improvement in the mechanical properties was found when the diamine/anhydride molar ratio in the ternary reactive blends was 0.5/1. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 516–522, 2003     

Poly(L‐lactide)/polypropylene blends: Evaluation of mechanical,thermal, and morphological characteristics

Poly(L lactide) (PLA) was blended with polypropylene (PP) at various ratios (PLA:PP = 90 : 10, 80 : 20, 70 : 30, and 50 : 50) with a melt‐blending technique in an attempt to improve the melt processability of PLA. Maleic anhydride (MAH)‐grafted PP and glycidyl methacrylate were used as the reactive compatibilizers to induce miscibility in the blend. The PLA/PP blend at a blend ratio of 90 : 10, exhibited optimum mechanical performance. Differential scanning calorimetry and thermogravimetric analysis studies showed that the PLA/PP/MAH‐g‐PP blend had the maximum thermal stability with the support of the heat deflection temperature values. Furthermore, dynamic mechanical analysis findings revealed an increase in the glass‐transition temperature and storage modulus with the addition of MAH‐g‐PP compatibilizer. The interaction between the compatibilizers and constituent polymers was confirmed from Fourier transform infrared spectra, and scanning electron microscopy of impact‐fractured samples showed that the soft PP phase was dispersed within the PLA matrix, and a decrease in the domain size of the dispersed phase was observed with the incorporation of MAH‐g‐PP, which acted as a compatibilizer to improve the compatibility between PLA and PP. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

The effect of epoxy and tetramethyl thiuram disulfide on melt‐grafting of maleic anhydride onto polypropylene by reactive extrusion

In this report, melt grafting of maleic anhydride (MAH) and epoxy resin onto polypropylene (PP) by peroxide‐initiated reactive extrusion has been investigated. As evidenced by Fourier transform infrared spectroscopy, both MAH and epoxy resin were successfully grafted onto PP through the reactions of MAH with PP and epoxy resin with MAH. It was found that tetramethyl thiuram disulfide could promote the grafting of MAH and inhibit the degradation of PP, as revealed by chemical titration and melt flow experiments, through prolonging the lifetime of the macroradical; meanwhile, epoxy resin could reduce the sublimation of MAH and the maximum grafting degree of MAH. Furthermore, the introduction of grafted products was found to enhance the mechanical properties of PP/glass fiber composites, and this influence was very significant at high grafting degrees with a high content of epoxy resin, which could be interpreted in terms of improved compatibility and adhesion at the interface. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43422.